1. Field of the Invention
The present invention relates to image slice alignment. More specifically, the present invention relates to the determination of shift information.
2. Related Art
In the field of biometric image analysis, traditional techniques sample an image, such as a fingerprint, as the image is moved or swiped across a sensing mechanism. This sensing mechanism, which could be a fingerprint sensor, captures partial images of the finger during a single swipe. This single swipe produces sets of data at different times and within different coordinate systems. Computer vision technology can then be used to reconstruct an image on the entire fingerprint by sampling these sets of data and combining the partial images to form a complete image of the fingerprint.
The process of transforming these different sets of data into one coordinate system is known to those of skill in the art as image registration. Registration is necessary in order to be able to compare, or integrate, the data obtained from different measurements.
Conventional image registration techniques fall within two realms of classification methods: (i) area-based and (ii) feature-based. The original image is often referred to as the reference image and the image to be mapped onto the reference image is referred to as the target image. For area based image registration methods, the technique looks at the structure of the image via correlation metrics, Fourier properties, and other means of structural analysis.
Techniques used in image registration can be inefficient and slow. Since a relatively large amount of information must be processed, computing shifts between image slices of complex images can be computationally intensive.
What is needed, therefore, are methods and systems that can increase the efficiency and speed of image registration techniques.